org.makumba.list.engine
Class ComposedQuery

java.lang.Object
  org.makumba.list.engine.ComposedQuery

Direct Known Subclasses:

ComposedSubquery

public class ComposedQuery
extends Object

An OQL query composed from various elements found in script pages. It can be enriched when a new element is found. It has a prepared Qyuery correspondent in a makumba database It may be based on a super query.

Version:

$Id: ComposedQuery.java 3527 2009-01-02 16:13:26Z rosso_nero $

Author:

Cristian Bogdan

Nested Class Summary

static interface

ComposedQuery.Evaluator Interface for an Evaluator which can evaluate expressions

Field Summary

(package private) String[]	derivedSections Derived section texts, made from the sections of this query and the sections of its superqueries
(package private) static Vector<Vector<Integer>>	empty A Vector containing an empty vector.
static int	FROM Standard index for the FROM query section
(package private) String	fromAnalyzerOQL
static int	GROUPBY Standard index for the GROUPBY query section
(package private) Vector<Integer>	keyset The keyset defining the primary key for this query.
(package private) Vector<String>	keysetLabels The labels of the keyset
static int	ORDERBY Standard index for the ORDERBY query section
(package private) Vector<Vector<Integer>>	previousKeyset The keyset of all the parent queries
(package private) Hashtable<String,Integer>	projectionExpr The expression associated to each projection
(package private) Vector<String>	projections The projections made in this query
QueryAnalysisProvider	qep
(package private) String[]	sections Section texts, encoded with the standard indexes
(package private) int	subqueries The subqueries of this query
(package private) String	typeAnalyzerOQL
static int	VARFROM Standard index for the VARFROM query section
static int	WHERE Standard index for the WHERE query section

Constructor Summary

ComposedQuery(String[] sections, String queryLanguage)
Default constructor

Method Summary

(package private) Integer	addProjection(String expr) Adds a projection with the given expression
void	addProjectionDirectly(String s) allows to directly set a projection.
protected void	addSubquery(ComposedSubquery q) Adds a subquery to this query.
void	analyze()
(package private) String	checkExpr(String str) Checks the orderBy or groupBy expressions to see if they are already selected, if not adds a projection.
Object	checkExprSetOrNullable(String expr)
(package private) String	checkProjection(String expr) Checks if a projection exists, and if not, adds it.
Integer	checkProjectionInteger(String expr) Checks if a projection exists, and if not, adds it.
static String	columnName(Integer n) Gets the name of a column indicated by index
protected String	computeQuery(String[] derivedSections, boolean typeAnalysisOnly) Computes the query from its sections
Grouper	execute(QueryProvider qep, Map args, ComposedQuery.Evaluator v, int offset, int limit) Executes the contained query in the given database
Map<String,DataDefinition>	getFromLabelTypes() Gets the types of the labels in the FROM section
String	getFromSection() Gets the FROM section
String	getGroupBySection() Gets the GROUP BY section
DataDefinition	getLabelType(String s) Gets the type of a given label
String	getProjectionAt(int n) Gets a given projection
Vector<String>	getProjections() Gets the projections of this query
DataDefinition	getProjectionTypes() Gets the type of the fields between SELECT and FROM
DataDefinition	getResultType() Gets the type of the result
String	getTypeAnalyzerQuery() Gets the query string.
void	init() Initializes the object.
protected void	initKeysets() Initializes the keysets. previousKeyset is "empty"
protected void	prependFromToKeyset() Adds all keys from the FROM section to the keyset, and their labels to the keyLabels.
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

qep

public QueryAnalysisProvider qep

subqueries

int subqueries

The subqueries of this query

projections

Vector<String> projections

The projections made in this query

projectionExpr

Hashtable<String,Integer> projectionExpr

The expression associated to each projection

FROM

public static final int FROM

Standard index for the FROM query section

See Also:

Constant Field Values

WHERE

public static final int WHERE

Standard index for the WHERE query section

See Also:

Constant Field Values

GROUPBY

public static final int GROUPBY

Standard index for the GROUPBY query section

See Also:

Constant Field Values

ORDERBY

public static final int ORDERBY

Standard index for the ORDERBY query section

See Also:

Constant Field Values

VARFROM

public static final int VARFROM

Standard index for the VARFROM query section

See Also:

Constant Field Values

sections

String[] sections

Section texts, encoded with the standard indexes

derivedSections

String[] derivedSections

Derived section texts, made from the sections of this query and the sections of its superqueries

typeAnalyzerOQL

String typeAnalyzerOQL

fromAnalyzerOQL

String fromAnalyzerOQL

keyset

Vector<Integer> keyset

The keyset defining the primary key for this query. Normally the primary key is made of the keys declared in FROM, in this query and all the parent queries. Keys are kept as integers (indexes)

previousKeyset

Vector<Vector<Integer>> previousKeyset

The keyset of all the parent queries

keysetLabels

Vector<String> keysetLabels

The labels of the keyset

empty

static Vector<Vector<Integer>> empty

A Vector containing an empty vector. Used for empty keysets

Constructor Detail

ComposedQuery

public ComposedQuery(String[] sections,
                     String queryLanguage)

Default constructor

Parameters:

sections -

usesHQL -

Method Detail

getResultType

public DataDefinition getResultType()

Gets the type of the result

Returns:

The DataDefinition corresponding to the type of the result

getLabelType

public DataDefinition getLabelType(String s)

Gets the type of a given label

Parameters:

s - the name of the label

Returns:

A DataDefinition corresponding to the type of the label

init

public void init()

Initializes the object. This is a template method

getFromSection

public String getFromSection()

Gets the FROM section

Returns:

A String containing the FROM section of the query

getGroupBySection

public String getGroupBySection()

Gets the GROUP BY section

Returns:

A String containing the GROUP BY section of the query

initKeysets

protected void initKeysets()

Initializes the keysets. previousKeyset is "empty"

addSubquery

protected void addSubquery(ComposedSubquery q)

Adds a subquery to this query. Makes it aware that it has subqueries at all.

Parameters:

q - the subquery

prependFromToKeyset

protected void prependFromToKeyset()

Adds all keys from the FROM section to the keyset, and their labels to the keyLabels. They are all added as projections (this has to change)

getProjectionAt

public String getProjectionAt(int n)

Gets a given projection

Parameters:

n - the index of the projection

Returns:

A String containing the projection

addProjection

Integer addProjection(String expr)

Adds a projection with the given expression

Parameters:

expr - the expression to add

Returns:

The index at which the expression was added

checkProjectionInteger

public Integer checkProjectionInteger(String expr)

Checks if a projection exists, and if not, adds it.

Parameters:

expr - the expression to add

Returns:

The index of the added projection

checkProjection

String checkProjection(String expr)

Checks if a projection exists, and if not, adds it.

Parameters:

expr - the expression to add

Returns:

The column name of the projection

columnName

public static String columnName(Integer n)

Gets the name of a column indicated by index

Parameters:

n - the index of the column

Returns:

A String containing the name of the column, of the kind "colN"

checkExpr

String checkExpr(String str)

Checks the orderBy or groupBy expressions to see if they are already selected, if not adds a projection. Only group by and order by labels.

Parameters:

str - an orderBy or groupBy expression

Returns:

The checked expression, transformed according to the projections

computeQuery

protected String computeQuery(String[] derivedSections,
                              boolean typeAnalysisOnly)

Computes the query from its sections

Parameters:

derivedSections - the sections of this query

typeAnalysisOnly - indicates whether this is only a type analysis

Returns:

The computed OQL query

execute

public Grouper execute(QueryProvider qep,
                       Map args,
                       ComposedQuery.Evaluator v,
                       int offset,
                       int limit)
                throws LogicException

Executes the contained query in the given database

Parameters:

qep - the database where the query should be ran

args - the arguments we may need during the execution

v - the evaluator evaluating the expressions

offset - at which iteration this query should start

limit - how many times should this query be ran

Throws:

LogicException

analyze

public void analyze()

addProjectionDirectly

public void addProjectionDirectly(String s)

allows to directly set a projection. Used for totalCount in QueryTag.doAnalyzedStartTag(org.makumba.analyser.PageCache) to compose a query with 'count(*)' as the only projection.

toString

public String toString()

Overrides:

toString in class Object

getTypeAnalyzerQuery

public String getTypeAnalyzerQuery()

Gets the query string.

Returns:

the query string in a form that can be used by a type analyser, in the query language of the ComposedQuery

getProjections

public Vector<String> getProjections()

Gets the projections of this query

Returns:

a Vector containing the projections of this ComposedQuery

getProjectionTypes

public DataDefinition getProjectionTypes()

Gets the type of the fields between SELECT and FROM

Returns:

A DataDefinition containing as fields the type and name of the query projections

getFromLabelTypes

public Map<String,DataDefinition> getFromLabelTypes()

Gets the types of the labels in the FROM section

Returns:

a Map containing the labels and their type

checkExprSetOrNullable

public Object checkExprSetOrNullable(String expr)